280 OPERATIONS SUBSIDIARY TO INDUCTION. 



be defined. But the names of elementary sensations, or 

 elementary feelings of any sort, cannot be defined; nor 

 is there any means of making their signification known 

 but by making the learner experience the sensation, or 

 referring him, through some known mark, to his re- 

 membrance of having experienced it before. Hence it 

 is only the impressions on the outward senses, or those 

 inward feelings which are connected in a very obvious 

 and uniform manner with outward objects, that are 

 really susceptible of an exact descriptive language. 

 The countless variety of sensations which arise, for 

 instance, from disease, or from peculiar physiological 

 states, it would be in vain to attempt to name; for as 

 no one can judge whether the sensation I have is the 

 same with his, the name may not have, to us two, any 

 community of meaning. The same may be said, to a 

 considerable extent, of purely mental feelings. But 

 in some of the sciences which are conversant with 

 external objects, it is scarcely possible to surpass the 

 perfection to which this quality of a philosophical 

 language has been carried. 



"The formation" (continues Mr. Whewell*) "of 

 an exact and extensive descriptive language for botany 

 has been executed with a degree of skill and felicity, 

 which, before it was attained, could hardly have been 

 dreamt of as attainable. Every part of a plant has 

 been named; and the form of every part, even the 

 most minute, has had a large assemblage of descriptive 

 terms appropriated to it, by means of which the bota- 

 nist can convey and receive knowledge of form and 

 structure, as exactly as if each minute part were pre- 

 sented to him vastly magnified. This acquisition was 

 part of the Linnsean reform. ... ' Tournefort,' says 



Philosophy of the Inductive Sciences, i., 465-7- 



